Feed valve for locomotives



April 5 1927.

G. DE GRAHL FEED VALVE FOR LOCOMOTIVES Filed March 11, 1925 Patented Apr. 5, 1927.

UNITED STATES PATENTVIO F F I C E GUSTAV DE GEAHL, or BERLIN-ZEI-ILENDORF-WEST, GERMANY. i

ram) VALVE FOR LOCOMOTIVES. I

l Application filed March 11,1825, Serial No. 14,818, and in Germany November 14, 1924.

Forlocomotives a device has already been suggested by means of which, when the regulatingv valve isclosed, individual groups -.of-accessories of the locomotive, such-as air supplied to these groups through a difierential control piston. It hasnow been found that certain of the accessory groups, such as the injectorsand the, auxiliary blower, are preferably worked only with wet steam, and

in the case of the known apparatus another special steam connection is therefore necessary, which holds wetsteam alone in storage and enables'itv to be supplied to the lastmentioned auxiliary groups. In the case of the known arrangement moreover there is the great danger that by the use of a super heated steam the heating hose pipes, which establish the connection between the individual carriages, are severely attacked and after ashorttime are destroyed.

These disadvantages are removed by the present invention, a feed valve for locomotives being provided which by its special constructionyrenders the steam connection for obtaining wet steam superfluous and on the other hand gives the possibility of adding a predetermined quantity of superheated steam to the wet steam employed for heating, that is to say, only just so much as is requisite in order toprevent condensation in the heating pipe, without the heating hose pipes thereby being particularly attacked.

The invention is illustrated by way of example in the accompanying drawing,

1 wherein Figure 1 is a longitudinal section through I the feed valve, and

Figure 2 an elevation thereof on a reduced scale.

According to the invention, spaces 2 and 3, separated from one another, are provided in the casing 1 of the feed valve. The feed valve is arranged in any desired position, at the steam dome or preferably on the boiler barrel, as shown in Figure 1, where 4 indicates the wall of the boiler. On the side facing the steam space 5 the feed valve is entirely open or preferably is provided with separate passages 6, shown in dotted lines in Figure 1, so that wet steam can flow through the feed valve in the direction of the arrow 6, the steam passing through a space 7 into the space 2 and from here steam can vented or limited should occasion require by y a screw spindle 12. The bore 10 communicates through a pipe 13 with the superheater chamber, and passages 14 are provided through which in one position of the difiierential control piston, the superheated steam from the superheater chamber can enter the space 3. Further passages 15 are arranged, which in the other position of the differential control piston allow wet steam to pass out of the chamber 2 into the space 3. Pipe unions 16 enable superheated steam to be taken out of the space 3, and in the case of a special constructional form, a pipe branched 011' from such a union 16 to an in jector 17, which is connected to a union 8 for Wet steam as shown in Figure 2.

The method of working of the apparatus is as follows:

If the regulating valve is opened, the superheated steam acts on the part of the differential control piston having the larger diameterso that the said piston is pushed towards one of its limiting positions and allows superheated steam to enter the space 3 through the passages 14. Consequently through the unions 16 superheated steam is made available for the feed and air pumps. Independently of this the space 2 is in constant communication with the wet steam from the boiler, which enters this space in the direction of the arrows 6, and this wet steam can be supplied through the pipe unions 8 to the other auxiliary groups, the injectors, the auxiliary blower, the steam heating apparatus and the like. Through the injector 17 some superheated steam can be drawn by suction out of the space 3 by the wet steam and fed to the wet steam, according to the adjustment of this ejector 17. In this manner the danger of damaging the heating hose pipes by raising the temperature of the Wet steam is obviated and at the same time condensation in the wet steam the pressure of the wet steam on the other side of the difierential control piston diswhen the regulating valve is opened. The

passages 14 are at the same time closed. so that the wet steam cannot escape here from the space 3.

\Vhat I claim is 1. A feed valve of the type for controlling the passage of superheated and wet steam respectively from a superheater and boiler to an injector comprising a casing having superposed chambers therein, the lower of which is provided with inlets for superheated and wet steam, each of said chambers being also provided with outlets, a differential cylinder in said casing arranged concentrically of both of said chambers, and a differential piston in said cylinder for controlling the passage of wet and superheated steam through said chambers and easing.

Q. A feed valve of the character described. comprising a casin a chamber arranged within the casing, a cylinder body in the casing having two coaxial bores of different widths, a differential piston mounted in the bores for controlling the passage of superheated steam from a heater to an injector, passages extending through the cylinder body communicating with the chamber, an out-let leading from the chamber, a second chamber in the casing, passages connecting the second chamber with the cylinder at points near the respective ends of the piston, an inlet for superheated steam for the second chamber and controlled by the lower part of the piston.

A feed valve for the type for controlling the passage of superheated and wet steam respectively from a superheater and boiler to an injector, comprising a casing provided with superposed chambers, the lower of which is provided with inlets for superheated and wet steam, both of said chambers being also provided with outlets, a differential cylinder body in said casing and arranged concentrically of both of said chambers, a differential piston in said cylinder for controlling the passage of wet and superheated steam through said chambers and easing, passages provided in the casing and cylinder body for conducting wet steam to the upper of said chambers, other passages provided in the casing adjacent the upper and lower ends of the lower chamner and both parts of said differential cylinder body and respectively controlled by the upper and lower parts of the piston.

A feed valve of the type set forth in claim 3, wherein a manually operable hand wheel is mounted in the casing for controlling the position of the piston.

A feed valve of the type for controlling the passage of superheated steam from a superheater to an injector. comprising a casing, a cylinder body within said casing provided with two coaxial bores of different width, a differential piston mounted in said bores. superposed chambers arranged in the casing about and above the cylinder body. the lower piston controlling the flow of superheated steam into said lower chamber, the upper chamber being in constant communication with the upper of said pistons. passages within the cylinder body for conducting wet steam to the upper chamber. an outlet leading from the lower chamber and adapted to be connected to the injector, and a second outlet in the upper chamber controlled by said upper piston for permitting wet steam to pass through the outlet to the injector. substantially as and for the purposes set forth.

In testimony whereof I have signed my name to this specification.

GUSTAV on GRAHL. 

